It can happen, yep. So long as you're sure you're not pregnant... don't worry too much.
Here comes the science bit...
Oestrogen is stored in fat cells. Very often, women who are overweight stop having periods, partly because of the high levels of oestrogen but also because of having high insulin levels (which can mess about with egg production in the ovaries).
When you lose weight quickly - fat, in particular - oestrogen is released from the fat cells. The body needs to have fluctuating levels of oestrogen to trigger the menstrual cycle. When oestrogen remains elevated, you don't have periods.
Your periods will stabilise when your weight stabilises. Of course, other people doing CD find that doing a low carb diet helps to regulate their periods. As I said before, this is because insulin levels affect the ovaries - a low carb diet keeps insulin levels low and the ovaries function normally once the fat mass reduces to a more healthy level. This is why low carb diets can be really useful for sufferers of some types of PCOS.
Hopefully I haven't made this even more confusing. The key thing is the level of oestrogen. High levels can either trigger periods that don't stop when you're expecting them to - or, as in your case, cause them not to happen at all. The good news is that in all probability, your body will sort itself out soon.